A liquid immersion microscope objective assembly includes an objective, a liquid delivery system for delivering an immersion liquid to a lens of the objective, and a liquid return system for removing liquid from an area around the lens. The objective may be positioned below a sample container. Liquid is delivered to the lens so as to form a bolus between the lens and the sample container. Excess liquid drains into the return system, which may be done via a notch or a V-shaped channel. Additionally, the direction of flow through the delivery system may be reversed, such that liquid may also be removed from the area around the lens via the delivery system. The assembly may also be utilized to remove liquid from the underside of the sample container. The assembly may also include a leak sensor and/or an electrowetting device.