On desktop (MacOS and Windows) or on Wire for Web:

In the conversation list:

1. Click the name of the person you'd like to call.
2. Click the Video Call  icon in the conversation to begin the call.
3. To end the call, click Hang Up .

Google Chrome, Mozilla Firefox, and Opera support video calls on Wire.

On mobile devices:

In the conversation list:

1. Tap the name of the person you'd like to talk to.
2. Tap Video Call   in the upper right corner of the conversation. 
3. To end the call, tap Hang up .