diff --git a/src/components/views/messages/MFileBody.js b/src/components/views/messages/MFileBody.js
index a1512738fd..e8c97e5f44 100644
--- a/src/components/views/messages/MFileBody.js
+++ b/src/components/views/messages/MFileBody.js
@@ -16,11 +16,11 @@ limitations under the License.
 
 'use strict';
 
-var React = require('react');
-var filesize = require('filesize');
-var MatrixClientPeg = require('../../../MatrixClientPeg');
-var sdk = require('../../../index');
-var DecryptFile = require('../../../utils/DecryptFile');
+import React from 'react';
+import filesize from 'filesize';
+import MatrixClientPeg from '../../../MatrixClientPeg';
+import sdk from '../../../index';
+import {decryptFile} from '../../../utils/DecryptFile';
 
 
 module.exports = React.createClass({
@@ -66,7 +66,7 @@ module.exports = React.createClass({
     componentDidMount: function() {
         const content = this.props.mxEvent.getContent();
         if (content.file !== undefined && this.state.decryptedUrl === null) {
-            DecryptFile.decryptFile(content.file).done((url) => {
+            decryptFile(content.file).done((url) => {
                 this.setState({
                     decryptedUrl: url,
                 });
diff --git a/src/components/views/messages/MImageBody.js b/src/components/views/messages/MImageBody.js
index 6784cede7a..4a3cfce591 100644
--- a/src/components/views/messages/MImageBody.js
+++ b/src/components/views/messages/MImageBody.js
@@ -23,7 +23,7 @@ import ImageUtils from '../../../ImageUtils';
 import Modal from '../../../Modal';
 import sdk from '../../../index';
 import dis from '../../../dispatcher';
-import DecryptFile from '../../../utils/DecryptFile';
+import {decryptFile} from '../../../utils/DecryptFile';
 
 
 module.exports = React.createClass({
@@ -44,10 +44,10 @@ module.exports = React.createClass({
     onClick: function onClick(ev) {
         if (ev.button == 0 && !ev.metaKey) {
             ev.preventDefault();
-            var content = this.props.mxEvent.getContent();
-            var httpUrl = this._getContentUrl();
-            var ImageView = sdk.getComponent("elements.ImageView");
-            var params = {
+            const content = this.props.mxEvent.getContent();
+            const httpUrl = this._getContentUrl();
+            const ImageView = sdk.getComponent("elements.ImageView");
+            const params = {
                 src: httpUrl,
                 mxEvent: this.props.mxEvent
             };
@@ -63,7 +63,7 @@ module.exports = React.createClass({
     },
 
     _isGif: function() {
-        var content = this.props.mxEvent.getContent();
+        const content = this.props.mxEvent.getContent();
         return (content && content.info && content.info.mimetype === "image/gif");
     },
 
@@ -107,7 +107,7 @@ module.exports = React.createClass({
         this.fixupHeight();
         const content = this.props.mxEvent.getContent();
         if (content.file !== undefined && this.state.decryptedUrl === null) {
-            DecryptFile.decryptFile(content.file).done((url) => {
+            decryptFile(content.file).done((url) => {
                 this.setState({
                     decryptedUrl: url,
                 });
@@ -135,14 +135,13 @@ module.exports = React.createClass({
             return;
         }
 
-        var content = this.props.mxEvent.getContent();
-
-        var thumbHeight = null;
-        var timelineWidth = this.refs.body.offsetWidth;
-        var maxHeight = 600; // let images take up as much width as they can so long as the height doesn't exceed 600px.
+        const content = this.props.mxEvent.getContent();
+        const timelineWidth = this.refs.body.offsetWidth;
+        const maxHeight = 600; // let images take up as much width as they can so long as the height doesn't exceed 600px.
         // the alternative here would be 600*timelineWidth/800; to scale them down to fit inside a 4:3 bounding box
 
         //console.log("trying to fit image into timelineWidth of " + this.refs.body.offsetWidth + " or " + this.refs.body.clientWidth);
+        var thumbHeight = null;
         if (content.info) {
             thumbHeight = ImageUtils.thumbHeight(content.info.w, content.info.h, timelineWidth, maxHeight);
         }
@@ -151,8 +150,8 @@ module.exports = React.createClass({
     },
 
     render: function() {
-        var TintableSvg = sdk.getComponent("elements.TintableSvg");
-        var content = this.props.mxEvent.getContent();
+        const TintableSvg = sdk.getComponent("elements.TintableSvg");
+        const content = this.props.mxEvent.getContent();
 
         if (content.file !== undefined && this.state.decryptedUrl === null) {
 
@@ -167,8 +166,8 @@ module.exports = React.createClass({
             );
         }
 
-        var contentUrl = this._getContentUrl();
-        var thumbUrl = this._getThumbUrl();
+        const contentUrl = this._getContentUrl();
+        const thumbUrl = this._getThumbUrl();
 
         if (thumbUrl) {
             return (
diff --git a/src/components/views/messages/MVideoBody.js b/src/components/views/messages/MVideoBody.js
index 4e60e17e40..c5fc0f9802 100644
--- a/src/components/views/messages/MVideoBody.js
+++ b/src/components/views/messages/MVideoBody.js
@@ -21,7 +21,7 @@ import MFileBody from './MFileBody';
 import MatrixClientPeg from '../../../MatrixClientPeg';
 import Model from '../../../Modal';
 import sdk from '../../../index';
-import DecryptFile from  '../../../utils/DecryptFile';
+import {decryptFile} from  '../../../utils/DecryptFile';
 
 module.exports = React.createClass({
     displayName: 'MVideoBody',
@@ -80,19 +80,19 @@ module.exports = React.createClass({
         if (content.file !== undefined && this.state.decryptedUrl === null) {
             var thumbnailPromise = Promise.resolve(null);
             if (content.info.thumbnail_file) {
-                thumbnailPromise = DecryptFile.decryptFile(
+                thumbnailPromise = decryptFile(
                     content.info.thumbnail_file
                 );
             }
-            thumbnailPromise.done((thumbnailUrl) => {
-                DecryptFile.decryptFile(
-                    content.file
-                ).then(function(contentUrl) {
-                    this.setState({
+            thumbnailPromise.then(function (thumbnailUrl) {
+                decryptFile(content.file).then(function(contentUrl) {
+                    return {
                         decryptedUrl: contentUrl,
                         decryptedThumbnailUrl: thumbnailUrl,
-                    });
+                    };
                 });
+            }).done((state) => {
+                this.setState(result);
             }, (err) => {
                 console.warn("Unable to decrypt attachment: ", err)
                 // Set a placeholder image when we can't decrypt the image.